To provide a small crawler type tractor which can be manufactured by utilizing a structure of a rear wheel-driven small wheel type tractor to the maximum extent possible, and enhance the productivity, fuel consumption, and durability of a bearing.

A crawler type traveling device having crawler frames for rotatably supporting a driven idler on both ends and a drive sprocket 60 fitted to an axle 89 while a crawler belt 95 being wrapped around between the driven idler and the drive sprocket 60 is provided on a lower part of a vehicle body. The driving force of a sub speed change shaft 45 by the power of an engine is transmitted to the drive sprocket 60 via a gear 47 provided on a rear end of the sub speed change shaft 45 and a gear 21 provided on a pinion shaft 22, and via a differential mechanism 50 from the pinion shaft 22.